1. Field of the Disclosure
Described herein are devices and methods for manipulating data storage media, particularly devices and methods for transporting storage media between or within storage media libraries.
2. Background
Automated storage systems, including cartridge libraries, are commonly used to store data storage media. One or more individual storage libraries may contain many data storage devices, as well as multiple media drives for reading from, and writing to the storage devices. Automated robotic devices may be used to move storage devices between the various storage cells, and to and from the media drives within the storage library. Individual storage devices may be indexed, and the entire system may be controlled by a device (or devices) capable of coordinating the movement of the storage devices.
One type of storage system includes two or more storage device libraries that may be linked together for coordinated control. With this type of system, each library may include a library housing, a plurality of storage devices (e.g., cartridges) stored in one or more storage device bins within the housing, at least one robotic handling mechanism, and one or more media drives. If multiple libraries are used as part of the same storage system, it may be desirable to coordinate the handling of storage devices between individual storage libraries. Moving storage devices between libraries may help avoid bottlenecks and delays. For example, if many storage devices in a storage library are requested at the same time, delays may result if the number of demanded storage devices exceeds the number of media drives, or the ability of the robotic handlers to process the demand. Thus, it may be desirable to distribute storage devices between libraries. Further, if one or more of the storage device drives in a library fails, it may be desirable to transfer storage devices to another library having functional drives.
Transfer mechanisms have been developed to transfer storage devices between storage libraries. These transfer mechanisms typically include hardware that provides or assists movement of storage devices between individual libraries. In general, simple and inexpensive transfer mechanisms take up useful space within a storage library (e.g., space that could contain other storage bins or media drives). For example U.S. Pat. No. 6,438,623 to Ryan (herein incorporated by reference in its entirety) describes a movable cartridge bin that moves in a straight line between the storage libraries, along a pathway that spans two or more storage libraries, and takes up useful space within the storage library.
Transfer mechanisms must be accessible to a robotic handler (or to some other data storage device manipulators) within each library cavity. However, the transfer mechanism must also move the data storage device between the libraries and avoid interfering with other portions of the library such as the storage bins or media drives. Practically speaking, a robotic handler within a storage library may have a limited range of motion, resulting in a finite amount of useful space within a storage device library that can be accessed by the robotic handler. Thus, it may be desirable to minimize the amount of useful space needed by the transfer mechanism.
Most transfer mechanisms capable of transferring storage devices between storage libraries include a track connecting the storage libraries. The storage device transfer mechanism typically moves in one dimension along the track, and therefore the track must take up useful space within the library cavity so that the transfer mechanism can be accessed by a robotic handler. For example, U.S. Pat. No. 5,760,995, U.S. Pat. No. 6,648,574, U.S. Pat. No. 6,751,040, U.S. Pat. No. 5,700,125, U.S. Pat. No. 6,574,173, and U.S. Pat. No. 6,438,623 describe transferring storage devices that move in only one dimension down a track. All of these references are herein incorporated by reference in their entirety.
Accordingly, there is a need for a simple storage device pass-through transfer mechanism. In particular, there is a need for a slider device having a misalignment tolerance that may provide two-dimensional motion from a single driver and may be configured as a shuttle to move and reliably extend and retract for loading and unloading of storage media. None of the cited prior art suggests the device and methods described and claimed below.